Pilot's Handbook of Aeronautical Knowledge (Federal Aviation Administration)

by Federal Aviation Administration

  Hazard and Risk

  Two defining elements of ADM are hazard and risk. Hazard is a real or perceived condition, event, or circumstance that a pilot encounters. When faced with a hazard, the pilot makes an assessment of that hazard based upon various factors. The pilot assigns a value to the potential impact of the hazard, which qualifies the pilot’s assessment of the hazard—risk.

  Therefore, risk is an assessment of the single or cumulative hazard facing a pilot; however, different pilots see hazards differently. For example, the pilot arrives to preflight and discovers a small, blunt type nick in the leading edge at the middle of the aircraft’s prop. Since the aircraft is parked on the tarmac, the nick was probably caused by another aircraft’s prop wash blowing some type of debris into the propeller. The nick is the hazard (a present condition). The risk is prop fracture if the engine is operated with damage to a prop blade.

  The seasoned pilot may see the nick as a low risk. He realizes this type of nick diffuses stress over a large area, is located in the strongest portion of the propeller, and based on experience; he does not expect it to propagate a crack that can lead to high risk problems. He does not cancel his flight.

  The inexperienced pilot may see the nick as a high risk factor because he is unsure of the affect the nick will have on the operation of the prop, and he has been told that damage to a prop could cause a catastrophic failure. This assessment leads him to cancel his flight.

  Therefore, elements or factors affecting individuals are different and profoundly impact decision-making. These are called human factors and can transcend education, experience, health, physiological aspects, etc.

  Another example of risk assessment was the flight of a Beechcraft King Air equipped with deicing and anti-icing. The pilot deliberately flew into moderate to severe icing conditions while ducking under cloud cover. A prudent pilot would assess the risk as high and beyond the capabilities of the aircraft, yet this pilot did the opposite. Why did the pilot take this action?

  Past experience prompted the action. The pilot had successfully flown into these conditions repeatedly although the icing conditions were previously forecast 2,000 feet above the surface. This time, the conditions were forecast from the surface. Since the pilot was in a hurry and failed to factor in the difference between the forecast altitudes, he assigned a low risk to the hazard and took a chance. He and the passengers died from a poor risk assessment of the situation.

  Hazardous Attitudes and Antidotes

  Being fit to fly depends on more than just a pilot’s physical condition and recent experience. For example, attitude affects the quality of decisions. Attitude is a motivational predisposition to respond to people, situations, or events in a given manner. Studies have identified five hazardous attitudes that can interfere with the ability to make sound decisions and exercise authority properly: anti-authority, impulsivity, invulnerability, macho, and resignation. [Figure 2-4]

  Hazardous attitudes contribute to poor pilot judgment but can be effectively counteracted by redirecting the hazardous attitude so that correct action can be taken. Recognition of hazardous thoughts is the first step toward neutralizing them. After recognizing a thought as hazardous, the pilot should label it as hazardous, then state the corresponding antidote. Antidotes should be memorized for each of the hazardous attitudes so they automatically come to mind when needed.

  Figure 2-4. The five hazardous attitudes identified through past and contemporary study.

  Risk

  During each flight, the single pilot makes many decisions under hazardous conditions. To fly safely, the pilot needs to assess the degree of risk and determine the best course of action to mitigate the risk.

  Assessing Risk

  For the single pilot, assessing risk is not as simple as it sounds. For example, the pilot acts as his or her own quality control in making decisions. If a fatigued pilot who has flown 16 hours is asked if he or she is too tired to continue flying, the answer may be “no.” Most pilots are goal oriented and when asked to accept a flight, there is a tendency to deny personal limitations while adding weight to issues not germane to the mission. For example, pilots of helicopter emergency services (EMS) have been known (more than other groups) to make flight decisions that add significant weight to the patient’s welfare. These pilots add weight to intangible factors (the patient in this case) and fail to appropriately quantify actual hazards, such as fatigue or weather, when making flight decisions. The single pilot who has no other crew member for consultation must wrestle with the intangible factors that draw one into a hazardous position. Therefore, he or she has a greater vulnerability than a full crew.

  Examining National Transportation Safety Board (NTSB) reports and other accident research can help a pilot learn to assess risk more effectively. For example, the accident rate during night visual flight rules (VFR) decreases by nearly 50 percent once a pilot obtains 100 hours and continues to decrease until the 1,000 hour level. The data suggest that for the first 500 hours, pilots flying VFR at night might want to establish higher personal limitations than are required by the regulations and, if applicable, apply instrument flying skills in this environment.

  Several risk assessment models are available to assist in the process of assessing risk. The models, all taking slightly different approaches, seek a common goal of assessing risk in an objective manner. The most basic tool is the risk matrix. [Figure 2-5] It assesses two items: the likelihood of an event occurring and the consequence of that event.

  Likelihood of an Event

  Likelihood is nothing more than taking a situation and determining the probability of its occurrence. It is rated as probable, occasional, remote, or improbable. For example, a pilot is flying from point A to point B (50 miles) in marginal visual flight rules (MVFR) conditions. The likelihood of encountering potential instrument meteorological conditions (IMC) is the first question the pilot needs to answer. The experiences of other pilots, coupled with the forecast, might cause the pilot to assign “occasional” to determine the probability of encountering IMC.

  Figure 2-5. This risk matrix can be used for almost any operation by assigning likelihood and consequence. In the case presented, the pilot assigned a likelihood of occasional and the severity as catastrophic. As one can see, this falls in the high risk area.

  The following are guidelines for making assignments.

  • Probable—an event will occur several times

  • Occasional—an event will probably occur sometime

  • Remote—an event is unlikely to occur, but is possible

  • Improbable—an event is highly unlikely to occur

  Severity of an Event

  The next element is the severity or consequence of a pilot’s action(s). It can relate to injury and/or damage. If the individual in the example above is not an instrument rated pilot, what are the consequences of him or her encountering inadvertent IMC conditions? In this case, because the pilot is not IFR rated, the consequences are catastrophic. The following are guidelines for this assignment.

  • Catastrophic—results in fatalities, total loss

  • Critical—severe injury, major damage

  • Marginal—minor injury, minor damage

  • Negligible—less than minor injury, less than minor system damage

  Simply connecting the two factors as shown in Figure 2-5 indicates the risk is high and the pilot must either not fly or fly only after finding ways to mitigate, eliminate, or control the risk.

  Although the matrix in Figure 2-5 provides a general viewpoint of a generic situation, a more comprehensive program can be made that is tailored to a pilot’s flying. [Figure 2-6] This program includes a wide array of aviation-related activities specific to the pilot and assesses health, fatigue, weather, capabilities, etc. The scores are added and the overall score falls into various ranges, with the range representative of actions that a pilot imposes upon himself or herself.

  Figure 2-6. Example of a more comprehensive risk assessm
ent program.

  Mitigating Risk

  Risk assessment is only part of the equation. After determining the level of risk, the pilot needs to mitigate the risk. For example, the pilot flying from point A to point B (50 miles) in MVFR conditions has several ways to reduce risk:

  • Wait for the weather to improve to good visual flight rules (VFR) conditions.

  • Take an instrument-rated pilot.

  • Delay the flight.

  • Cancel the flight.

  • Drive.

  One of the best ways single pilots can mitigate risk is to use the IMSAFE checklist to determine physical and mental readiness for flying:

  1. Illness—Am I sick? Illness is an obvious pilot risk.

  2. Medication—Am I taking any medicines that might affect my judgment or make me drowsy?

  3. Stress—Am I under psychological pressure from the job? Do I have money, health, or family problems? Stress causes concentration and performance problems. While the regulations list medical conditions that require grounding, stress is not among them. The pilot should consider the effects of stress on performance.

  4. Alcohol—Have I been drinking within 8 hours? Within 24 hours? As little as one ounce of liquor, one bottle of beer, or four ounces of wine can impair flying skills. Alcohol also renders a pilot more susceptible to disorientation and hypoxia.

  5. Fatigue—Am I tired and not adequately rested? Fatigue continues to be one of the most insidious hazards to flight safety, as it may not be apparent to a pilot until serious errors are made.

  6. Emotion—Am I emotionally upset?

  The PAVE Checklist

  Another way to mitigate risk is to perceive hazards. By incorporating the PAVE checklist into preflight planning, the pilot divides the risks of flight into four categories: Pilot-in-command (PIC), Aircraft, enVironment, and External pressures (PAVE) which form part of a pilot’s decision-making process.

  With the PAVE checklist, pilots have a simple way to remember each category to examine for risk prior to each flight.

  Once a pilot identifies the risks of a flight, he or she needs to decide whether the risk, or combination of risks, can be managed safely and successfully. If not, make the decision to cancel the flight. If the pilot decides to continue with the flight, he or she should develop strategies to mitigate the risks. One way a pilot can control the risks is to set personal minimums for items in each risk category. These are limits unique to that individual pilot’s current level of experience and proficiency.

  For example, the aircraft may have a maximum crosswind component of 15 knots listed in the aircraft flight manual (AFM), and the pilot has experience with 10 knots of direct crosswind. It could be unsafe to exceed a 10 knot crosswind component without additional training. Therefore, the 10 knot crosswind experience level is that pilot’s personal limitation until additional training with a certificated flight instructor (CFI) provides the pilot with additional experience for flying in crosswinds that exceed 10 knots.

  One of the most important concepts that safe pilots understand is the difference between what is “legal” in terms of the regulations, and what is “smart” or “safe” in terms of pilot experience and proficiency.

  P = Pilot in Command (PIC)

  The pilot is one of the risk factors in a flight. The pilot must ask, “Am I ready for this trip?” in terms of experience, recency, currency, physical, and emotional condition. The IMSAFE checklist provides the answers.

  A = Aircraft

  What limitations will the aircraft impose upon the trip? Ask the following questions:

  • Is this the right aircraft for the flight?

  • Am I familiar with and current in this aircraft? Aircraft performance figures and the AFM are based on a brand new aircraft flown by a professional test pilot. Keep that in mind while assessing personal and aircraft performance.

  • Is this aircraft equipped for the flight? Instruments? Lights? Navigation and communication equipment adequate?

  • Can this aircraft use the runways available for the trip with an adequate margin of safety under the conditions to be flown?

  • Can this aircraft carry the planned load?

  • Can this aircraft operate at the altitudes needed for the trip?

  • Does this aircraft have sufficient fuel capacity, with reserves, for trip legs planned?

  • Does the fuel quantity delivered match the fuel quantity ordered?

  V = EnVironment

  Weather

  Weather is a major environmental consideration. Earlier it was suggested pilots set their own personal minimums, especially when it comes to weather. As pilots evaluate the weather for a particular flight, they should consider the following:

  • What is the current ceiling and visibility? In mountainous terrain, consider having higher minimums for ceiling and visibility, particularly if the terrain is unfamiliar.

  • Consider the possibility that the weather may be different than forecast. Have alternative plans and be ready and willing to divert, should an unexpected change occur.

  • Consider the winds at the airports being used and the strength of the crosswind component.

  • If flying in mountainous terrain, consider whether there are strong winds aloft. Strong winds in mountainous terrain can cause severe turbulence and downdrafts and be very hazardous for aircraft even when there is no other significant weather.

  • Are there any thunderstorms present or forecast?

  • If there are clouds, is there any icing, current or forecast? What is the temperature/dew point spread and the current temperature at altitude? Can descent be made safely all along the route?

  • If icing conditions are encountered, is the pilot experienced at operating the aircraft’s deicing or anti-icing equipment? Is this equipment in good condition and functional? For what icing conditions is the aircraft rated, if any?

  Terrain

  Evaluation of terrain is another important component of analyzing the flight environment.

  • To avoid terrain and obstacles, especially at night or in low visibility, determine safe altitudes in advance by using the altitudes shown on VFR and IFR charts during preflight planning.

  • Use maximum elevation figures (MEFs) and other easily obtainable data to minimize chances of an inflight collision with terrain or obstacles.

  Airport

  • What lights are available at the destination and alternate airports? VASI/PAPI or ILS glideslope guidance? Is the terminal airport equipped with them? Are they working? Will the pilot need to use the radio to activate the airport lights?

  • Check the Notices to Airmen (NOTAM) for closed runways or airports. Look for runway or beacon lights out, nearby towers, etc.

  • Choose the flight route wisely. An engine failure gives the nearby airports supreme importance.

  • Are there shorter or obstructed fields at the destination and/or alternate airports?

  Airspace

  • If the trip is over remote areas, is there appropriate clothing, water, and survival gear onboard in the event of a forced landing?

  • If the trip includes flying over water or unpopulated areas with the chance of losing visual reference to the horizon, the pilot must be prepared to fly IFR.

  • Check the airspace and any temporary flight restriction (TFRs) along the route of flight.

  Nighttime

  Night flying requires special consideration.

  • If the trip includes flying at night over water or unpopulated areas with the chance of losing visual reference to the horizon, the pilot must be prepared to fly IFR.

  • Will the flight conditions allow a safe emergency landing at night?

  • Perform preflight check of all aircraft lights, interior and exterior, for a night flight. Carry at least two flashlights—one for exterior preflight and a smaller one that can be dimmed and kept nearby.

  E = External Pressures

  External pressures are influences external to the flight that crea
te a sense of pressure to complete a flight—often at the expense of safety. Factors that can be external pressures include the following:

  • Someone waiting at the airport for the flight’s arrival

  • A passenger the pilot does not want to disappoint

  • The desire to demonstrate pilot qualifications

  • The desire to impress someone (Probably the two most dangerous words in aviation are “Watch this!”)

  • The desire to satisfy a specific personal goal (“get-home-itis,” “get-there-itis,” and “let’s-go-itis”)

  • The pilot’s general goal-completion orientation

  • Emotional pressure associated with acknowledging that skill and experience levels may be lower than a pilot would like them to be. Pride can be a powerful external factor!

  Managing External Pressures

  Management of external pressure is the single most important key to risk management because it is the one risk factor category that can cause a pilot to ignore all the other risk factors. External pressures put time-related pressure on the pilot and figure into a majority of accidents.

  The use of personal standard operating procedures (SOPs) is one way to manage external pressures. The goal is to supply a release for the external pressures of a flight. These procedures include but are not limited to:

  • Allow time on a trip for an extra fuel stop or to make an unexpected landing because of weather.

  • Have alternate plans for a late arrival or make backup airline reservations for must-be-there trips.

  • For really important trips, plan to leave early enough so that there would still be time to drive to the destination, if necessary.